grandma and daughter embracing and smilingGetting a “Sleep Apnea Detroit” is hard enough, especially so for stroke survivors. While various studies have been performed to determine the relationship between the two, physicians continue to miss the signs.  In fact, according to a review published in the American Heart Association’s journal Stroke, more than 50% of stroke survivors have some type of sleep disorder, yet few are formally tested (in part due to this lack of awareness).  Sleep disorders that may have been present and undiagnosed before a stroke can worsen significantly afterwards. So, if we can increase awareness and testing (and therefore diagnosis) of sleep disorders, a number of strokes could end up being prevented.
Stroke is a condition in which there is an acute neurologic occurrence as a result of ischemic cerebral infarction (87% of strokes) or brain hemorrhage (13% of stroke).  Blood vessels become dilated., hemorrhages may be seen, and edema may form.  Stroke can also cause brain ischemia and hemorrhage into the brain.
In brain hemorrhage, there can be bleeding directly into the brain parenchyma, which is called intracerebral hemorrhage. If bleeding occurs in the cerebrospinal fluid within the subarachnoid space, this is known as subarachnoid hemorrhage.

Ichemic stroke pertains to having very little blood supply to provide parts of the brain with enough oxygen and nutrients, while hemorrhagic stroke pertains to too much bleeding within the enclosed cranial cavity. A transient ischemic attack often called a mini stroke.  OSA is related to stroke, because moderate-to severe OSA is associated with silent ischemic changes.
There are three subtypes of brain ischemia.
-Thrombosis refers to local obstruction of an artery.
-Embolism pertains to debris formed elsewhere that causes an obstruction.
-Systemic hypoperfusion results from a systemic circulatory problem manifesting itself in the   brain and other organs of the body

It has been reported that more than 70% of stroke survivors have OSA.  Without REM sleep, you have less of a chance of recovery from stroke because your body never gets refreshed and recharged.  This can lead to high blood pressure as well, which is the strongest risk factor associated with stroke, and unfortunately another reason that the connection between OSA and stroke is missed. Again, it becomes the chick and the egg scenario – what happened first?
If sleep apnea increases the risk of stroke, either directly or indirectly, untreated patients with comorbid OSA may have worse functional outcomes and higher mortality after acute stroke.
A very high prevalence of SDB (69–77%) has also been reported in patients who have had a stroke, but because sleep studies were not performed before the strokes, it is not possible to determine which came first, the SDB or the stroke.
When it comes time to decide on the treatment plan for OSA/SDB – depending on the level of severity either the CPAP or an intraoral appliance can be utilized (or a combination of both).

Moderate-to-severe OSA is also significantly associated with hypertension.  Effective treatment of OSA significantly reduces blood pressure, thus reducing the chance for stroke.
Stroke is the most common cause of long-term disability in the United States (over 1 million people affected), and the healthcare costs associated with stroke are astronomical.  By raising awareness in the healthcare community, hopefully more of the relationships between the signs and symptoms and OSA and stroke will be recognized and addressed.
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